Sound-record-recording device



Fatented Aug. 31, 1926.

sari-star FRANK X. HOFIBAUER, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO THE BRUNSWICK- BALKE-COLLENDER OUMPANY, OF CHICAGG, ILLINOIS, A CORTORATION OF DIELA- W'ARE.

SOUND-RECOED-BECORDING DEVICE.

Application filed May 2,

This invention relates to improvements in devices or apparatus for making sound records and its object is to provide an improved recording device which is adapted for making a sound groove of the lateral undulatory type in suitable record material by a displacing operation as distinguished from a cutting out operation, and to produce a well defined record groove with smooth walls which will enable the reproduction of t-e sound from a suitable commercial finished record disc with a superior tone quality and more nearly reproducing the original sound than has been customary heretofore.

In the accompanying drawings, T have illustrated a selected embodiment of the invention and referring thereto Fig. 1 is a side elevation.

Fig. 2 is a front elevation.

Fig. 3 is a top plan view.

Fig. 1 is a sectional view on the line H of Fig. 2.

Fig. 5 is an enlarged sectional view on the line 5-5 of Fig. 1.

'Fig. 6 is a detail sectional view.

The invention comprises a frame of suit able character which, in the embodiment illustrated, consists of the member 6 which is provided with an opening 7 communicating with an integral nipple 8 to which the usual horn 9 is suitably attached. The diaphragm 10 is mounted in a suitable manner on the member 6 and this diaphragm may be of any suitable material and it may be mounted in any manner approved in the art. The other member 11 of the frame is fastened rigidly to the diaphragm member by screws or bolts 12 and is of skeleton shape and provided with aligned recesses 13 in which a stylus bar 14 is supported to rock on suitable bearings 15. The stylus bar has a laterally projecting tubular arm 16 which is joined with the diaphragm centrally thereof by a connection 17, which may be integral with the arm 16. These parts have been made of aluminum and there is a slight flexibility in the arm and connection which is desirable. The stylus baris also connected by a spring 18 with an adjustable stud 19 on'a projection 19 rigid with the skeleton frame member 11. The stylus bar projects below the skeleton frame member and carries a forwardly projecting arm 20 in which the stylus 21 is mounted at a 1922. Serial No. 553,011.

reverse or negative angle to displace the material of the recording blank with a trailing action as distinguished from a cutting out operation. The arm 20 is cylindrical in shape and is rigidly connected to the lower end of the stylus bar and the stylus is mounted in the forward free end of this arms which is substantially parallel with the face of the recording blank, as indicated by the line 22 in Fig. 1.

In the operation of. the apparatus it has been customary to revolve the record blank relatively to this recording device and tofeed the recording device radially of the blank to produce a spiral groove in the blank. This is common practice in the are and need not be further described.

In my device spring 18 normally holds the rocking stylus bar, the diaphragm and the stylus in rigid position with relation to each other and movements of the diaphragm as produced in the usual manner of recording are transmitted from the diaphragm to the stylus through the connecting parts, which includes the rocking stylus bar, without loss or distortion to produce a lateral movement of the stylus corresponding to the movements of the diaphragm. The spring also holds the rocking stylus bar against its pivots 15 which are mounted in the integral bracket portions 11 of the skeleton frame member 11-. At the same time the stylus is displacing the material from the record ing blank due to the engagement of the stylus therewith and to the relative movement of the blank and this displacing operation produces a record groove in the blank which is calculated to form the foundation for the product-ion of a commercial finished record disc which will provide in a suitable machine a reproduction of superior tone quality more nearly resembling the sounds as recorded than has been customary heretofore.

T mount the device or apparatus herein shown and described in a suitable recording machine, which I do not deem it necessary to illustrate or further describe, so that the diaphragm will be rocked transversely of the record groove, and with the stylus arm 20 projecting forwardly from' the stylus bar substantially normal to the diaphragm and substantially parallel with the face of the record blank so that the sound waves entering the horn will directly engage or affect the diaphragm without being bent or otherwise distort-ed in an angular or tortuous passage; and the movements of the diaphragm are communicated to the stylus through rigid connections to produce a record corresponding to the original sounds as near as may be possible and without loss or distortion.

I prefer to make the stylus arm 20 tubular for strength and rigidity and I connect it rigidly to the lower end of the stylus bar. A transverse opening 20 is provided in this arm to receive the stylus and the stylus is secured in this opening by means of shellac or other material which will hold the stylus rigidly in place and yet permit it to be readily and easily replaced or adjusted. The hollow stylus arm permits sufficient shellac or other cementing material to enter therein and help to secure the stylus rigidly in place, but of course some. of the shellac or other cementing material will or may be accumulated around or on the end of the arm to engage the stylus. v

I prefer to arrange. the stylus arm in the manner shown parallel with the face of the blank to make it tubular as described and shown, because I find this provides the rigidity which is desirable for securing a proper groove.

I am aware that changes in the form and construction and arrangement of the several parts of my invention may be made without departing from the spirit or sacrificing the advantages thereof and I reserve the right to make all such changes as fall within the scope of the following claims.

I also prefer to make the connection between the rocking bar and the diaphragm slightly flexible, as stated, and to-make the arm 16 tubular for strength as in the case of arm 20, combined with lightness in weight.

I claim:

- 1. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame in front of the diaphragm, spaced rocking pivots supported in the frame for said stylus bar and arranged in front thereof, a spring connected to. the stylus bar and the frame to hold the stylus bar against its pivots, connections between the diaphragm and the stylus bar, the connections being disposed intermediate the spacedrocking pivots and a stylus carried by the stylus bar.

2. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame and connected to the diaphragm, a tubular arm carried by the stylus bar, and a stylus mounted in said tubular arm transversely thereof.

3. A sound recording device comprising a frame, a diaphragm mounted in the frame,

a rocking stylus bar mounted in the frame and connected intermediate its ends to the diaphragm, a tubular arm connected at one end to the lower end of the stylus bar, and a stylus mounted in the other end of said arm transversely thereof. I

a. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame and arranged to rock about an axis parallel to the diaphragm, means connecting the stylus bar to the diaphragm, a tubular arm connected to. the lower end of the stylus bar and projecting forwardly thereof and substantially normal to the diaphragm, and a stylus mounted in said arm and arranged to move about the axis of the stylus bar in a plane substantially parallel to the surface upon which sounds are to be recorded, the stylus extending transversely through said tubular arm.

5. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame and connected to the diaphragm, rocking pivots supported in the frame for said stylus bar and arranged in front thereof, a spring connected to said. stylus bar and the frame to hold the stylus bar against its pivots, an arm on said stylus bar, a stylus on said arm mounted at a reverse or negative angle to operate on a moving record blank in a trail- =ing position to displace material from the blank in forming a record groove. 7

6. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus barmounted in the frame, spaced rocking pivots supported in the frame for said stylus bar and arranged in front thereof, a spring connected to the stylus bar and the frame to hold the stylus bar against its pivots, flexible means connecting the bar and the diaphragm, an arm on the bar, the flexible means being disposed intermediate the spaced rocking pivots, and a stylus mounted. on the arm.

7. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame, spaced rocking pivots supported in the frame for said stylus bar and arranged in front thereof, a spring connected to, the stylus barand the frame to hold the stylus bar against its pivots, a tubular arm on said bar disposed intermediate the rocking pivots, a connection between the arm and diaphragm, another arm on the bar,v and a stylus mount ed in the latter arm,

8. A sound recording device comprising a frame, a diaphragm moanted in the frame, a rocking stylus bar mounted in the frame, spaced rocking pivots supported in the frame for said stylus bar and arranged in front thereof, a spring connected to the stylus bar and the frame to hold' the stylus bar against its pivots, a tubular arm on said har disposed intermediate the rocking pivots, a connection between said arm and the diaphragm, another tubular arm on the bar, and a stylus mounted in the latter arm trans versely thereof.

9. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame in front of the diaphragm, spaced rocking pivots supported in the frame for said stylus bar and arranged in front thereof, a spring connected to the stylus bar and the frame to hold the stylus bar against its pivots, a tubular arm carried by said stylus bar and disposed intermediate the rockin pivots, flexihle means connecting said tubular arm with the diaphragm, a second tubular arm connected to the lower end of the stylus bar and projecting forwardly thereof in a plane substantially normal to the diaphragm, and a stylus mounted in said second tubular arm transversely thereof.

10. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame in front of the diaphragm and substantially parallel thereto, a connection between the diaphragm and the bar, an arm extending from the lower end of the bar and substantially normal to the diaphragm, and a stylus supported in said arm.

11. A sound recording device comprising a frame, a diaphragm mounted in the frame, a rocking stylus bar mounted in the frame in front of the diaphragm and substantially parallel thereto, a connection between the diaphragm and the bar, an arm extending from the lower end of the bar and substantially normal to the diaphragm, a stylus supported in said arm, and a spring normally holding said bar against rocking movement in respect to said diaphragm.

In testimony whereof I hereto affiX my signature.

FRANK 7X. HOFBAUER. 

